uh_overturning_rou: Critical wind speed for overturning - Roughness method.

Description Usage Arguments Value

View source: R/cws_rou_overturning.R

Description

Calculates the critical wind speed for overturning using the roughness method.

Usage

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uh_overturning_rou(
  mean_ht,
  mean_dbh,
  spacing,
  dist_edge,
  gap_size,
  mean_cr_width,
  mean_cr_depth,
  moe,
  c_reg,
  n_drag,
  c_drag,
  drag_upper_limit,
  stem_vol,
  stem_density,
  crown_density,
  snow_depth,
  snow_density,
  ro,
  fgr_constants
)

Arguments

mean_ht

Arithmetic mean height of the trees in the stand (m).

mean_dbh

Mean dbh of all trees in the stand (cm). Dbh is diameter at breast height, measured at 1.3m above the ground. Essential.

spacing

Mean distance between trees (m).

dist_edge

Distance from the upwind edge (m).

gap_size

Length of the upwind gap (m).

mean_cr_width

Width of the crown of the mean tree in the stand (m).

mean_cr_depth

Depth of the crown of the mean tree in the stand (m).

moe

Modulus of Elasticity of green wood (MPa).

c_reg

Regression coefficients of uprooting moment against stem weight (N m kg-1).

n_drag

N parameter of the drag coefficient formula (dimensionless).

c_drag

C parameter of the drag coefficient formula (dimensionless).

drag_upper_limit

Maximum wind speed used during the experiments from which n_drag and c_drag were derived (m*s-1).

stem_vol

Stem volume of the mean tree in the stand (m^3).

stem_density

Density of green wood of the stem (kg m-3).

crown_density

Crown density of the mean tree in the stand (kg m-3).

snow_depth

Depth of layer of snow on tree crown (cm).

snow_density

Density of snow (kg m-3).

ro

Air density (kg m-3).

Value

A list including: The critical wind speed (m s-1) for overturning at zero plane displacement height for the roughness method; The applied bending moment; The zero plane displacement height; The ratio of critical wind speed at canopy top over friction velocity (uh / u*); The deflection loading factor; The critical overturning moment; The combined effect of edge, gap, and gust on the applied bending moment.


tom-locatelli/fgr documentation built on Oct. 2, 2020, 2:09 a.m.